The pipe fitting is intended to be slipped over the end of a pipe to which it is to be connected, preferably with the interposition of a sealing ring, such as an O-ring. The fitting is then circumferentially squeezed or compressed from the outside to form a tight joint with the inwardly located pipe element. This circumferential compression can be done, for example, by compression jaws, rolling, or the like.
The pipe fitting must be formed with an inner groove in order to accommodate the sealing element, typically the O-ring. This requires deformation of the material of the pipe fitting. The deformation must not weaken the material of the fitting because, otherwise, leakage or other damage might result. It is, therefore, desirable that the pipe fitting fits the respective pipe ends, with which it is to be used, as accurately as possible before compression, so that excessive deformation of the pipe fitting when placed in use is not required.
Compression pipe fittings of this type are used in large numbers for installations of piping systems. Typically, these fittings are used for water pipes in a wide variety of sizes, for example from fractional inch sizes on up. A large number of such fittings are used, and thus it should be possible to make them at low cost.
The pipe and pipe fittings should, preferably, be of the same material so that the materials do not have different electrochemical potentials, resulting in possible corrosion at their juncture.
The circumferentially compressible pipe fitting has a tube-shaped connecting portion which receives an end of the pipe with which it is to be connected. This connecting portion has an outwardly bulged portion, defining an inner circumferential recess. The circumferential recess receives a sealing element, such as the O-ring, to effect a tight sealing connection between the pipe fitting and the connecting pipe, once the pipe fitting is circumferentially squeezed about the pipe. Typically, the connecting pipe is of sturdy material and, itself, not readily deformable, e.g. standard copper, brass, steel, black-iron, or other types of piping material.